1. Field of the Invention
The present invention generally relates to an apparatus and method for pre-baking a substrate such as a semiconductor wafer upstream of a process chamber, wherein the pre-baking is conducted to remove moisture from a film such as a resist film before processing the film.
2. Description of the Related Art
In order to bake out moisture, etc. from a film (such as a film including a resist film), after loading a wafer to a process chamber, the film is pre-baked and degassed before processing the wafer in the process chamber. Since the process chamber is used for the pre-baking and degassing process, regardless of the type of the process chamber (a single-wafer reactor or batch reactor), a wafer run rate or throughput is decreased due to the time used for pre-baking and degassing in the process chamber. Further, since the process chamber is controlled at a low pressure, and thermal conductivity and transfer are low under a reduced pressure, heating in the reduced pressure is not as efficient as in atmospheric pressure, requiring a longer time to raise and control the temperature. This also contributes to a reduction of wafer run rate or throughput.
An object of the present invention is to conduct pre-baking without suffering a throughput reduction.
Any discussion of problems and solutions in relation to the related art has been included in this disclosure solely for the purposes of providing a context for the present invention, and should not be taken as an admission that any or all of the discussion was known at the time the invention was made.